The J-Machine multicomputer: An architectural evaluation

The MIT J-Machine multicomputer has been con-structed to study the role of a set of primitive mechanisms in providing efficient support for parallel computing. Each J-Machine node consists of an integrated multicomputer component, the Message-Driven Processor (MDP), and 1 MByte of DRAM. The MDP provides mechanisms to sup-port efficient communication, synchronization, and nam-ing. A 512 node J-Machine is operational and is due to be expanded to 1024 nodes in March 1993. In this pa-per we discuss the design of the J-Machine and evaluate the effectiveness of the mechanisms incorporated into the MDP. We measure the performance of the communication and synchronization mechanisms directly and investigate the behavior of four complete applications.